Centrifuge



J l 7, 1959 c. H. WILKINSON; JR 2,893,627

CENTRIFUGE Filed Nov. 27, 1957 INVENTOR lkzns'any z States Patent Toe cumruruor:

Cecil H. Wi]kins'on, Jr., Victor-ville, Calif. I 1 Application November 27, 1957, Serial No. 699,297

l ..2 Claims. c 233-14 invention relates to a novel centrifuge for separating minerals .or thickening slurries and comprises a machine of novel construction utilizing centrifugal force, buoyancy and variations in specific gravities of the materials acted upon to elfectthe desired separation.

More particularly, it is an aim of the present invention to provide a machine of extremely simple construction involving a number of parts and which due to its unique construction is capable of separating particles of dilferent specific gravities and of separating, a liquid medium inwhich the particles are initially carried from said particles.

A further object of chine capable of being supported by a shaft or similar element by means of which rotation is imparted to the machine and wherein there is no relative movement between any of the parts of the assembled machine.

'Various other objects and advantages of the invention will hereinafter become more fully apparent from the following description of the ,drawing illustrating a presently preferred embodiment thereof, and wherein:

Figure 1 ,is a fragmentary plan view, partly in section, t h c n if ge;...-

the invention is to provide a maplates and 11 and the 2,893,627 Patented July ,7, 1959 wall 13 for securing the shell 14rto said'plates. Spacing elements 16 are mounted on the fastenings 15 between the plates 101 and 11 and betweenthe plate 11 and shell wall 13 for maintaining a proper spacing between said parts. It will thus be ap- I parent that the fastenings 15 and spacers 16 could also stituting the axis ofthe centrifuge 6, and are disposed extends downwardly to below the level of the plate 10.

An annular bottom wall 20- of the shell 14 extends in wardly from the bottom edge of the outer wall 19 and has a downwardly curved annular lip 21 defining the inner portion thereof and which is disposed beneath and spaced froman outer portion of the larger plate 10 and the bottom edge of which defines an outer opening 22 of the centrifuge 6. Said bottom wall 20 is substantially flat between its downturned lip 21 and the shell wall 19 and said flat portion extends inwardly to a point beneath the peripheral portion of the larger plate 10 and is spaced therefrom a distance preferably less than Figure 2 is an enlarged fragmentary diametrical sec tional view thereof, partly in elevation, taken substantially radial sectional I,

the spacing between the peripheral portion of the plate 10 and the top wall 13, as clearly illustrated in Figures 2 and 4. As illustrated in the drawing, the outer wall 19 at its lower edge has an outturned flange 23 against,

around the plates 10 and 11. However, the wall 20' could be formed integral with the wall 19 and the wall 19 could be detachably fastened to the top wall 13.

maybe provided with any suitablebearing support 8 andwhich may be rotatably driven in any suitable or conventional manner, such as by a belt and pulley drive 9, as seen inFigure 2.

Two. discs or plates 10 and 11 are mounted on the shaft 7. The plates 10 and 11 are both shown in Figure 2 fixed to the shaft 7 at 12 and disposed in spaced apart relation to one another. However, as the description proceeds it will be apparent that either plate could be opening 18.

26 is secured to the under or outer side of the plate 10 between the fastenings 15 and openings 25. The shield The smaller end of a frusto-conical shield 26 is disposed concentrically within and spaced from the outerdischarge opening 22. The larger end of the shield 26 forms an inner discharge opening 27 which is spaced a substantially greater distance from the plate 10 than f a by. l As'surning that/the shaft 7 is being driven to refixed to the shaft 7 and could support the other plate.

and with the larger plate 10 disposed beneath the plate 11. However, as the description proceeds it will become apparent that it is not essential that the shaft be disposed vertically or the plates horizontally,.although the materials to be treated can be more readily fed to and discharged from the centrifuge 6 when the centrifuge is disposed in substantially a horizontal plane, as illustrated.

annular top wall 13'of a shell orvcasing 14 of thecentrifug volv'e vthe centrifuge 6 and that a desired r.p.m. has;

been bbt ained, a heavy liquid is fed into the centrifuge throughthe inlet 18 in sufiicient quantity to fillthe annula'r'chamber 28 formed by the outer portions of the above and beneath the plate 10, as seen in Figure 4,-1.

is designated 29 and 30, respectively.

A mixture to be separated including a liquid such v water and particles of different specific gravities is then fed into'the centrifuge 6 through the inlet 18. The

heavyliquid-29, 30 selected to be utilized with-the par-I e. p a lessgthanlcertain of the; particles and greater thanthe Bolts of bolt and nut'fastenings 15 extend through" the other particles; "The'mixtur'e will initially'be'urged Outn wardly between the upper shell wall 13 and the smaller water baflle plate 11. The particles in the mixture .will

shell wall 19inthe chamber 28. The cake. 31 oflighter particles is porous and as this cake builds up in radial.

thickness-the outermostpart of the cake is pressed radially'outward and is submerged beneath the surface 29 of the heavy liquid until the outer portion thereof protrudes. beyond the periphery of the larger solid "ba'flie' plate 10. As this outer portion of the cake 31 becomes deprived of the support of the baffle plate 10, said cake portioncrumbles and the particles thereof, which; are of lower'specific gravity than the heavy liquid in the chamber 28-, float around the periphery of the plate 10 and are -forced by the specific gravity of the heavy liquid in a direction radially inward of the centrifuge and through the lower surface 30 of the heavy liquid. In this man-- ner a cake 33 ofthe lighter particles builds up between the battle plate 10 and the annular lip 21. The cake 33 is not sufiiciently supported by the lip 21 so that a portion of the cake 33 which is submerged inthe surface 30 will extend as far as-the periphery of the baffle plate 10. As the cake 33 builds up to form an angle approximately as shown in Figure 4, the bottom portion thereof will crumble around the edge of the lip 21 and will be discharged through the outer discharge opening 22 and will be thrown radially away from the centrifuge, as indicated at 34. The radial extent of the lip 21 will determine the size of the cake 33, and said lip 21 must-be of a proper size so that the cake 33 cannot'build up to a sufficient size to clog the centrifuge. The pressure of the water behind the inner wall of the cake 31 and also the pressure of the heavy particles 32 which are embedded in the cake 31 and are passing outwardly therethrough cause the cake 31 to exert a greater pressure against the liquid in the chamber 28 than the cake 33, so that the surface 29 of the heavy liquid is disposed nearer the periphery of the plate 10 than the surface 30 of said liquid. Additionally, the heavy particles which are embedded in and which work through the cakef31 assist in causing the outer wall of the cake 31 to crumble so that the lighter particles thereof will float around the periphery of the bafile plate 10 and enter the cake 33 as the heavier particles 32 are collected in the chamber 28.

The water of the mixture which is fed to the centrifuge 6 after passing beyond the periphery of the smaller water bafile plate 11 will be forced radially inwardly between the baflle plates 10 and 11 by the greater pressure of the cake 31 and by the pressure of additional mixture being fed into the centrifuge. The water thus separated from the mixture will back up between the plates 10 and 11 toward the axis of the centrifuge until the accumulated water reaches the openings 25. As the water reaches the openings 25 it will be discharged therethrough into the shield 26 and due to the fact that said shield is flared away from'the plate 10 the water will be deflected by the shield toward its open end and will be discharged from the inner discharge opening 27 and thus separated from the lighter particles being discharged as seen at 34. The separation and discharge of the water from the mixture is indicated by the arrows 35 in Figures 2 and 4. The water and the lighter particles discharged at 34 constitute two products separated by the centrifuge, both of which constitute a continuous separation while the centrifuge is in operation. Operation of the centrifuge is interrupted from time to time for removing the particles 32 0f greater specific gravityv from thechamber 28.

Anyfine particles which remain in suspension in the water and which go throughthe centrifuge without settling out will be so minute that the centrifugal force at the periphery of the water bafile plate 11 will be insuflicient to effect the separation. Accordingly the size of such particles remaining in and being discharged with the water can be varied by varying the diameter of the water separating plate 11 or by changing the rotational velocity of the centrifuge.

If it is only desired to separate particles from a liquid and not to efiect a separation between particles of different specific gravities, as in taking waterfrom a slurry, the specific gravity ofthe heavy liquid in the chamber 28 may be muchgreater than the specific .gravities of the particles and mercurymay be used as the heavy liquid. When the centrifuge is thus utilized, the operation thereof may be continuous since there will be no collection of particles in the chamber 28.

Various modifications and changes are contemplated and may be resorted to, without departing fromthe-function .or scope .of the invention as hereinafter defined'by the appended-claims. i

I claim as my'invention 1. A centrifuge for effecting separation of particles containedin a liquid mixture comprising, a rotary driven shaft, a first plate, :a second plate, said platesbeing mounted onsaid shaft, at least oneof said plat'e s'being fixed to the shaft for rotation therewith, a shell in which said plates are disposed having a wall" disposed parallel to the plates and'havin'g a icentrallydisposed opening constituting the inlet of the centrifuge, means engaging said wall and plates and-connecting the plates to one another and to the'shell and "spacing" the plates from one another and said *secondpla'te from said shell walland cooperating with the plate secured to the shaft for mounting the plates and shell concentrically around the shaft and rigid- 1y with respect thereto, said second plate being disposed betweenthe first plate and said shell 'wall'and being of smaller diameter than the first plate, said inlet opening being disposed concentrically around "and spaced from the shaft and being of smaller diameter than the second plate, said shell having a cylindrical outer wall extending from theperiphery of'the first mentioned shell wall and disposedconcentrically around and spaced outwardly from the periphery of the firstplate, said she'll having an annular wall extending inwardly from said cylindrical wall and having an inner edge terminating inwardly with respect to the periphery of said first plate-and of large'r diameter than said second plate, the peripheral portion of said first plate being disposed between and spaced from the first mentioned and'lastmen'tioned shell walls, the outer portion of the first mentioned shell wallcombining with the last mentioned shell wall-and said cylindrical wall to form an inwardly opening annular chamberinto which the peripheral portion of the first plate extends, portions of said plates and a portion of the'first mentioned shell wall forming an annular passage connecting the annular chamber-to said inlet, and parts ofthe last mentioned ws'hellwall and the first plate [forming an annular inwardly opening outlet ofthe centrifuge, aheavy liquid retained by centrifugal 'force in said annular chamber and in which the periphery of the first plate is submerged, said first plate'having a ring of spaced openings forming a circle of lesser diameter than the second plate and "constituting water separating'ports, and a frusto-conical shield having a restricted end securedit'o saidfirst plate around the openings thereof, said shield being of substantially smaller diameter than the "inner diameter of -the last mentioned shell'wall and extending from the first plate in a direction away trom said second 'plate and having a larger. opposite end defining a water 'discharge'out-j let of 'th'e centrifuge, said'wa'ter discharge outlet being spaced a substantially. greater "distance'from 'the'plane of said firstplate than said annularinwardly opening outlet;

' 2'. "A' centrifuge for effecting separation ofparti'clescon tained in, a liquid mixture comprising, a rotary shaft, a shell disposed around said shaft including a cylindrical outer wall and spaced annular walls extending inwardly from the outer wall, one of said annular walls being of substantially greater radial width than the other annular wall and having a central opening forming the inlet of the centrifuge, the other narrower annular Wall having an opening of larger diameter than said inlet opening and forming an outlet opening of the centrifuge, two plates of different diameters mounted concentrically around the shaft and disposed within said shell, at least one plate being fixed to the shaft, fastening means connecting the plates to one another and to the shell and positioning the plates in spaced substantially parallel relation to one another and spaced from and substantially parallel to said annular shell walls, said plate of smaller diameter being disposed between the inlet opening and the larger plate and being of a diameter less than the diameter of said discharge opening, the larger plate being of a diameter greater than the diameter of the discharge opening and extending into an annular inwardly opening chamber formed by said cylindrical wall and annular shell walls, and a heavy liquid retained by centrifugal force in said chamber and of a depth such that the peripheral portion of the larger plate is submerged in the liquid, said smaller plate being of larger diameter than the inlet opening, said larger plate having discharge openings therein spaced from the axis of the centrifuge a distance less than the radius of the smaller plate, and a shield having one end secured to the larger plate around said discharge openings thereof and extending from said plate in a direction away from the smaller plate, said shield being of smaller diameter than said outlet of the shell and being flared toward its opposite outlet end, said out-' let end of the shield being spaced a substantially greater distance from the larger plate than the outlet of the shell.

References Cited in the file of this patent UNITED STATES PATENTS 1,456,934 Rice May 29, 1923 

